New York Preservation Archive Project
Built Works Registry of architectural works and the built environment.
Historic House Trust information on historic houses located within NYC Parks.
Municipal Art Society of New York City Accidental Skyline, an interactive tool to demystify city planning.
New York City Community Boards discrete governmental bodies that oversee zoning and municipal buildings in NYC.
New York City Department of Buildings includes information about construction and building codes, licensing and permits.
New York City Landmarks Preservation Commission designates the City's landmarks and historic districts, and regulating changes to historic buildings.
Real Estate Record, historic weekly reports of NYC building activity from 1868-1922, digitized by Columbia University.
Sweets Network provides a deep library of thousands of Product Catalogs from leading building product manufacturers.